Mechanism for screening or sifting granulated substances



x A.-WALKER. M'ECNIANISM FOR SCREENING 0B SIFTING GRANULAi'ED SUBSTANCES.

APPLICATION FILED [MI- 30, I915- RENEWED JAN. 31, I921.

1,389,231. Patented Aug. 30,--1921.- S

s SHEETS-SHEET 1.

A. WALKER. MECHANISM FOR SCREENlNG 0R SIFTING GRANULATED SUBSTANCES.

APPLICATION FILED MAR. 30, I915. RENEWED JAN. 31, 1921- 1,389,231 Patented Aug. 30, .192

5 SHEETS-SHEET 2- @WWM A WALKER.

MECHANISM FOR SCREENING 0R SIFTING GRANULATED SUBSTANCES.

APPLICATION HLED MAR. 30, 1915- RENEWED JAN. 31, I921.

Patented Aug. 30, 1921.

5 SHEETS-SHEIET a.

A. WALKER.

MECHANlSM FOR SCREENING 0R SIFTING GRANULATED SUBSTANCES. APEucAnoN FILED MAR. 30, 1915. RENEWED JAN, 31, 1921.

1 89,233 1 I Patented Aug. 30, 1921.

5 SHEETS-SHEET 4.

EN /m 6Q h L v 1 Q I \\B\ NEW/0g A. WALKER.

MECHANISM FOR SCREENING 0E SIFTING GRANULATED SUBSTANCES.

Patehted Aug. 30, 1921. 5 SHEETS-SHEET 52 [UNITED STATES PATENT OF'FI; CE.;

aLEXAivnER WALKER, or wALLsnNn-UroN-rYNn, ENGLAND, assieivon or oma HALF TO nna cnsmivurnn. or.ovmvnmv;HALIFAxnNenANn MECHANISM FORSCREENING OR SIFTING'GRANULATED SUBSTANCES Specification of Letters Patent. 'Patented Aug. 30, 1921.

"Application filed March 30,1915, Serial No. 18,174. Re ewed January 31, 1921. Serial No. 441,502.

"To all whom it may concern:

. Be it known that I, ALEXANDER WALKER,

, a subject of the King of Great Britain, and residing at Donwal, Kings.Road,Wallsend on-Tyne, in the county of Northumberland, England, have inventedcertain new and useful Improvements in Mechanism for 1 Screening or Sifting Granulated Substances,

-of whiohthe following description, having a 10 reference to the annexed sheets of drawings,

- is a specification- I l I v In the screening or s fting of coke, coal,

; crushed stonev and other granulated subscreen- I stances it is often desirable that the particl'es of matter should have imparted to them a rolling movement in order that other and smaller particles'adheringgto one side or the other of same may be thrown off. In apparatus wherein rotary sieves or screens as -heretoforeconstructed are employed it, is found that said rollingand 'other motions areso violent asto considerably damage or .y'blBELk up the substances being treated and especially is that the case in the-screening .01" sifting ofcokea In, other forms of 1 screens where longitudinal bars of a step like character have been used the effect we.

1 desire has not been attained since said bars have had interstices or spaces adjoining them throughout the length of the screen; or {have had screening surfaces adjoining them produced by perforations'being made A through flat base platesnone of which formations; permit the rolling and other mo- :tions ofthe substances being treated that I 4 secure by my devices. c. V

. v The object of myinvention is. to obviate these disadvantages and produce apparatus that will carry out the actions desired and 40 these I secure by forming my screening surfaces, consisting of series of projections or fingers with plain or blankparts intervening V between them, in-such manner that same do not in any way impair or deteriorate the substances being treated but which permit such substances to travel over themwith the rollingfand other motions-described, while the, ;extent to which said motions are imparted to saidsubstances maybe regulated to be .increasedor decreased as may be found necessary.

'In carrying my invention into effect I ,make use of apparatus or. mechanism illustrated by the accompanying sheets of drawings, wherein Figure l is a side "sectional elevation (taken on line C-D of Fig. 2) of a sieve and its hopper or chute constructed in ac cordance with my said invention.

1g. 2 is a plan ofthe parts shown by Fig. 1. i

ig. 3 is. a. side sectionalelevation of a sieve or screen of the reciprocating type.

Fig. 4-;is a plan of theparts shown by Fig.3., w

Fig. 5 i s/a side elevation of a revolving Fig. '6 isanend elevation of said screen showing the, operating shaft section,

' Figs. 7 and Sare sectional elevation and plan drawn to an enlargedscale showing 1n detailthe method of. constructing my im-' -p vedscreen with, what may be termed,

stationary screening devices. 7

Figs. 9 and 10 are sectional side elevation and plan showing how certain of my improved parts may beadjusted. f

Fig. llisa drawing inidetail hereinafter described. r i

Fig. 12 shows a portion of the mechanism illustrated by Fig. 5 but of a'modified construction hereinafter described.

Toattain the object of my invention, ac-

cording to one arrangement I'make use of appropriate framework A upon which I may mount an inclined sieve or screen formed with blank parts a and open parts a while at the outer edges of these are the sides a which guide the substances over said screen as they descend from the hopper Z) into whichjthey fall and from which they escape as will be understood. Thus on the granulated substances which have to bescreened being placed in the receptacle?) when the door or cover 0" is raised asyshown by Fig.1, said granulated substanceswill descend"and spread over the whole surface'of the'sc'reen as they travel over same. Thescreening surface is formed by having spaces a to alternate between the blank parts or base plates at (said spaces andfplates being of appropriatewidth) while overhangingthose spaces a? and at an angle to the base plates (6 of the screenjIhave projections'or fingers a3.

The outer ends of these fingers cl, as shown by Figs; 2 8 at d are narrower thanare their bases at d thus the slots 6 between them are broader at their outer than they are at their inner ends, by which formationwhen the granulated substances are traveling or rolling over the blank parts a on encountering the fingers d the smaller particles will pass between said fingers while the larger particles will roll over and descend beyond same on to the succeeding portion of the screens blank parts a. In this manner said larger particles get rid of or discharge the smaller particles by these latter falling or passing through the openings 6 to-descend to the ground or floor beneath, while the taper formation of the fingers prevents the wedging of any particles between them by reason them on to the return chute 7, thus the small.

particles or screenings will all beconducted into the space between the uprights A, while the particles that have been separated from said screenings will pass beyond the outer end a of the screen.

fingers cl with intervening blank parts a may be followed in producing and making use of a screen that has reciprocatory motion transmitted toit, thus the screen illustrated by Figs. 3 and 4c is mounted upon the pendent connecting rods 9 which are supported from the framework B, while reciprocatory mot1on is transmitted to said swlnging screen or sieve from the rotary shaft it upon Which is fixed the eccentric hhby said eccentric operating the sieve a by means ofits connecting rod h The granulated substances to be treated are supplied to the sieve down the chute lc.

Instead of the fingers (i being fixed to the" base or blank parts a of the screen they may be mounted upon pivots as d shown by Figs. 9 and 10, so that by loosening the fixing bolt m which takes through the quadrant slot m 1n the fixed bracket m? the fingers cl may be adjusted at any angle relatively with the base a and when so adjusted'may be secured by the bolt m being firmly screwed or tightened up.

The base of the screen and the side walls thereof as well as the finger pieces may be ofany appropriate kind of metal, as steel or the like or the finger pieces cl may be .of cast metal or of other formation asmay be found advantageous. V V I V Leading to the screens hereinbefore describedare the hopper b and chute k respectively and the orifices or openings 12 through which. the granulated substances have to pass when leavingsaid chutes, are considerably narrower than the width of the screens as shown by Figs. 2 and 4 of the drawings, by which arrangement, as the granulated substances descenddownthe chutes in considerable'thickness on escaping therefrom on to the base of the screen they separate or spread laterally to cover the whole surface or width of said screen and are thus more effectively treated thereby.

I have hereinbefore described my invention as for use in connection with flat inclined surfaces but I can also apply my improved formation of screening devices to cylindricalscreens of the character illustrated by Figs. 5, 6 and 12' Here the screen is mounted upon a shaft qsto which motion is transmitted through gearing wheels 1' and 7' from a main or other driving shaft 8. 1

The bases p upon which fingers d are formed or fixed or from which they extend, form the base of the screen and the actions of the fingers d are in this case similar to the actions of the fingers d in the former conangles from theedges of the bases 12 as "shown by Fig. 5, while according to another arrangement the extend, as shown in Fig.

1 12 at such an ang e thereto as will cause them The same arrangement and formation of to point or extend in the opposite direction to the rotations of the cylindrical screen as shown by Fig. 12. p

The supp-lying of the granulated substances to the rotary screen is effected through the chute t.

Although I have illustrated and described the projections 'd as extending from the base parts a so as to have free outer ends d it is obvious that such projecting parts may be made to extend from one base part a to the next below as'shown'by Fig. '11, and that they may or may not be fixed or secured to said adjoining base part. 7 Such being the nature and object of my said invention what I claim is 1. Mechanism for cleaning and sifting granulated substances comprising a screen formed with alternating bottom portions and openings, each opening extending transversely of the screen, said bottom portions being inclined and lying in the same plane, a plurality of screening fingers on one edge of each bottom portion, said fingersbeing upwardly'inclined relatively to the bottom portion and projecting in thedirection of travel of the said substances with their free ends overhanging the adj acent bottom portion beyondthe opposing edge thereof, each bottomportion extending for a considerable distance from the finger overlapped edge thereof to its opposite edge, for providing extended flooring sections. 7

2. Mechanism for cleaning and sifting granulated substances, a screen element including bottom sections with intervening adjustably mounted projections or fingers, and operable means for actuating and maintaining said projections o-r fingers at any desired angle re ative to said bottom sections of screen.

3. In mechanism for screening or sifting granulated substances, a screen for screening or sifting operations, a plurality of series of teeth extending at an angle from the surface of said screen, blank parts intervening between said series of teeth, and means for adjustably varying the angles of the teeth of each series simultaneously.

4:. In mechanism for screening or sifting granulated substances, a screen for screening or sifting operations pivotally adjustable teeth extending from the surface of said screen, blank parts intervening between said teeth, an operable means for actuating and maintaining said teeth at any desired angle relative to said blank parts forming the bottom of the screen.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

ALEXANDER WALKER.

Witnesses:-

ALLEN G. WARREN, SAMUEL HEY. 

